The invention relates to an integrated circuit arrangement with a sensor element, and in particular to an integrated circuit sensor such as a magnetic field transducer that provides an encoded output signal on an integrated circuit lead.
Integrated circuit arrangements with sensor elements (e.g. with magnetic sensors) that detect mechanical switching states in a large number of consumer and automotive applications are known. They detect a mechanical switching state by a variable magnetic field, which represents the changed position on the basis of a variable distance between the magnetic field sensor and a movable magnet. The physical variable of magnetic field strength is thus used as a measure for determining the switching state. If the magnet approaches the transducer, which converts the magnetic field strength into an analog electrical signal, the switching state “turned on” is represented at the output of the sensor circuit when the distance becomes less than a certain distance A1. If the distance becomes less than a further distance A2, the output signal represents “turned off”. This clearly shows that this sensor circuit can represent a switching state as either “turned on” or “turned off”. If more switching states are required, it is necessary to use a cascade of such sensor circuits. However, this results in a complex circuit structure that is relatively bulky, expensive and unreliable. Furthermore, such total circuits have a high EMC risk, which is a great disadvantage in the automotive field.
Therefore, there is a need for an integrated circuit sensor that receives an input signal and compares the input signal against a number of threshold values to determine the switching state efficiently within the integrated circuit.